In order to elucidate the mechanisms involved in the inhibition of puerarin on spontaneous-and stimulated-contractions of rat myometrium, strips of Sprague Dawley rat uterus were suspended in tissue chambers to measure the isometric tension.Puerarin dose-dependently inhibited the tonic and spontaneous contractions of uterine muscle strips, which were partly blocked by glibenclamide, ICI118551, N-nitro-L-arginine but had no obvious changes prior treatment with SQ22536.Puerarin could also dose-dependently inhibit PGF2α-induced contractions but did not affect the concentration-response curve of CaCl2 in Ca2+-free solution containing EGTA.The results demonstrate that puerarin can inhibit uterine contractile response which maybe benefits for dysmenorrhea.Inhibitions of puerarin on uterine contractions possibly involve in adrenergic β2 receptor, ATPsensitive K+ channel and nitric oxide (NO) release but are not related to cAMP synthesis and the Ca2+ influx.